cover slips with poly-L-lysine/poly-L-ornithine

Hi, I'm working whit fluorescence in LNCaP cells but I have problems to cell attachment in cover slips. I will try with cover slips coated with poly-L-lysine, poly-L-ornithine and a mixture of both. My question is if somebody has a protocol to coat the slips both poly-L-lysine/poly-L-ornithine. Thank you for your time!!!